Shared error detection and correction memory

ABSTRACT

Apparatuses and methods of sharing error correction memory on an interface chip are described. An example apparatus includes: at least one memory chip having a plurality of first memory cells and an interface chip coupled to the at least one memory chip and having a control circuit and a storage area. The control circuit detects one or more defective memory cells of the first memory cells of the at least one memory chip. The control circuit further stores first defective address information of the one or more defective memory cells of the first memory cells into the storage area. The interface chip responds to the first defective address information and an access request to access the storage area in place of the at least one memory chip when the access request has been provided with respect to the one or more defective memory cells of the first memory cells.

BACKGROUND

High data reliability, high speed of memory access, lower powerconsumption and reduced chip size are features that are demanded fromsemiconductor memory. In recent years, three-dimensional (3D) memorydevices have been introduced. Some 3D memory devices are formed bystacking chips (e.g., dice) vertically and interconnecting the chipsusing through substrate vias (TSVs). Benefits of the 3D memory devicesinclude shorter interconnects which reduce circuit delays and powerconsumption, a large number of vertical vias between layers which allowwide bandwidth buses between functional blocks in different layers, anda considerably smaller footprint. Thus, the 3D memory devices contributeto higher memory access speed, lower power consumption and chip sizereduction. Example 3D memory devices include Hybrid Memory Cube (HMC),High Bandwidth Memory (HBM), and a wide-I/O dynamic random access memory(DRAM).

For example, High Bandwidth Memory (HBM) is a type of memory including ahigh-performance DRAM interface and vertically stacked DRAM. A typicalHBM stack of four DRAM chips (e.g., core chips) has two 128-bit channelsper chip for a total of eight input/output channels and a width of 1024bits in total. An interface (I/F) chip of the HBM provides an interfacewith the eight input/output channels, which function independently ofeach other. For example, a clock frequency, a command sequence, and datacan be independently provided for each channel. Thus, the eightinput/output channels are not necessarily synchronous to each other.

There are several types of tests which may be performed for the HBM. Forexample, a type of test can be performed using a memory Built-In SelfTest (mBIST) circuit that may be provided on the I/F chip. The mBISTcircuit is provided for verifying failures resulting from stacking thechip. The mBIST circuit may include a memory to store defect informationcalled an error-catch memory (ECM). Using the defect information, forexample, hard repair such as blowing fuse to disconnect rows and columnswith faulty bits and replacing them with redundant rows or columns maybe performed.

The HBM has a post package repair function performed by using the mBISTcircuit. The post package repair function uses redundancy cells forrepair and these redundancy cells are normally formed in memory matricesof the core. However, the post package repair function may not be ableto repair defects if the number of defective cells is greater than anumber of repairable cells by providing redundancy cells. Furthermore,it may be difficult to repair one or more defective cells which areredundancy cells.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic diagram of an interface (I/F) chip and aplurality of core chips in a semiconductor device in accordance with anembodiment of the present disclosure.

FIG. 1B is a schematic diagram of a memory system including thesemiconductor device that includes the interface (I/F) chip and theplurality of core chips in accordance with an embodiment of the presentdisclosure.

FIG. 2 is a block diagram of the I/F chip in the semiconductor device inaccordance with an embodiment of the present disclosure.

FIG. 3 is a block diagram of the interface circuit in FIG. 2 including amemory Built-In Self Test (mBIST) circuit in the semiconductor device inaccordance with an embodiment of the present disclosure.

FIG. 4A is a simplified flow diagram of a test operation process by themBIST in FIG. 3 in the semiconductor device in accordance with anembodiment of the present disclosure.

FIG. 4B is a simplified flow diagram of a test operation as a part of aninitialization operation process performed by the mBIST in thesemiconductor device in accordance with an embodiment of the presentdisclosure.

FIG. 5 is a schematic diagram of the data input/output circuit of FIG.3, in accordance with an embodiment of the present disclosure.

FIG. 6 is a schematic diagram of the access signal output circuit ofFIG. 3, in accordance with an embodiment of the present disclosure.

FIG. 7A is a schematic diagram of a portion of the MEM of FIG. 3, inaccordance with an embodiment of the present disclosure.

FIG. 7B is a schematic diagram of a portion of the MEM of FIG. 3, inaccordance with an embodiment of the present disclosure.

FIG. 7C is a schematic diagram of a portion of the MEM of FIG. 3, inaccordance with an embodiment of the present disclosure.

FIG. 7D is a schematic diagram of a portion of the MEM of FIG. 3, inaccordance with an embodiment of the present disclosure.

FIG. 8 is a block diagram of the I/F chip including a memory Built-InSelf Test (mBIST) circuit in the semiconductor device in accordance withan embodiment of the present disclosure.

FIG. 9 is a schematic diagram of one core chip of the plurality of corechips in the semiconductor device in accordance with an embodiment ofthe present disclosure.

FIG. 10 is a block diagram of the I/F chip including a memory Built-InSelf Test (mBIST) circuit in the semiconductor device in accordance withan embodiment of the present disclosure.

FIG. 11A is a simplified flow diagram of a write operation in the I/Fchip of FIG. 10, in accordance with an embodiment of the presentdisclosure.

FIG. 11B is a simplified flow diagram of a read operation in the I/Fchip of FIG. 10, in accordance with an embodiment of the presentdisclosure.

FIG. 12 is a block diagram of the I/F chip in the semiconductor devicein accordance with an embodiment of the present disclosure.

FIG. 13 is a block diagram of the I/F chip in the semiconductor devicein accordance with an embodiment of the present disclosure.

FIG. 14A is a simplified flow diagram of a write operation in the I/Fchip of FIG. 13, in accordance with an embodiment of the presentdisclosure.

FIG. 14B is a simplified flow diagram of a read operation in the I/Fchip of FIG. 13, in accordance with an embodiment of the presentdisclosure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Various embodiments of the present invention will be explained below indetail with reference to the accompanying drawings. The followingdetailed description refers to the accompanying drawings that show, byway of illustration, specific aspects and embodiments in which thepresent invention may be practiced. These embodiments are described insufficient detail to enable those skilled in the art to practice thepresent invention. Other embodiments may be utilized, and structure,logical and electrical changes may be made without departing from thescope of the present invention. The various embodiments disclosed hereinare not necessary mutually exclusive, as some disclosed embodiments canbe combined with one or more other disclosed embodiments to form newembodiments.

FIG. 1A is a schematic diagram of an interface (I/F) chip and aplurality of core chips in a semiconductor device in accordance with anembodiment of the present disclosure. For example, the semiconductordevice 10 may be a 3D memory device, such as an HBM, an HMC, a Wide-IODRAM etc. The semiconductor device is formed by stacking chipsvertically, as shown in FIG. 1A. The stacked chips may include aninterface chip 21 and core chips 22. In this example, each core chip 22may be a memory chip which includes two channels. Each channel mayinclude a plurality of memory cells and circuitries accessing the memorycells. For example, the memory cells may be DRAM memory cells.

FIG. 1B is a schematic diagram of a memory system including thesemiconductor device that includes the interface (I/F) chip and theplurality of core chips in accordance with an embodiment of the presentdisclosure. The memory system 1 may include a memory controller 11 andthe 3D memory device 10. In this example, the core chips 22 a, 22 b, 22c and 22 d include channels A and C, channels B and D, channels E and G,and channels F and H, respectively. As shown in FIG. 1B, the channels A,B, C, D, E, F, G and H of the core chips 22 may be coupled to the I/Fchip 21 via different signal lines 23 a, 23 b, 23 c, 23 d, 23 e, 23 f,23 g, and 23 h, respectively. The I/F chip 21 may include test controlterminals 24, data terminals 25 and access signal terminals 26 whichreceive corresponding signals from a memory controller 11. For example,the test control terminals 24 may receive test control signals. The dataterminals 25 may receive write data from the memory controller 11 or maytransmit read data to the memory controller 11. The access signalterminals 26 may receive access signals from the memory controller 11.The access signals may include an operation command (e.g., a readcommand, a write command) and address information corresponding to theoperation command.

FIG. 2 is a block diagram of an interface circuit on the I/F chip 21 inthe semiconductor device in accordance with an embodiment of the presentdisclosure. An interface circuit 31 is provided on the I/F chip 21. Theinterface circuit 31 may include channel interface blocks CIF_A 32 a,CIF_B 32 b, . . . and CIF_H 32 h which are coupled to correspondingchannels, channel A, channel B, . . . and channel H of the core chip 22in FIG. 1B. Furthermore, the interface circuit 31 may include aplurality of data through substrate vias, TSVDs 33 and access throughsubstrate vias TSVAs 34. The TSVDs 33 and TSVAs 34 are configured tocouple the channel interface blocks CIF_A 32 a, CIF_B 32 b, . . . andCIF_H 32 h to the channels, channel A, channel B, . . . and channel H ofthe core chip 22 in FIG. 1B, respectively. In one embodiment, eachsignal line 23 in FIG. 1B may include the corresponding TSVD 33 and TSVA34 for each channel. Each channel interface block of the channelinterface blocks CIF_A 32 a, CIF_B 32 b, . . . and CIF_H 32 h mayinclude a data input/output circuit DI/O 35 and an access signal outputcircuit ASO 36. Each DI/O 35 may receive data from the coupled channelvia the corresponding TSVD 33. The DI/O 35 may be further coupled todata terminals DT 37. The data terminals DT 37 may be the data terminals25 in FIG. 1B. The ASO 36 may be coupled to access signal terminals AT38. The access signal terminals AT 38 may receive access signalsincluding access requests provided externally (e.g., from the memorycontroller 11 of FIG. 1B). Each access request may include a commandincluding an operation requested (e.g., a read request, a write request,etc.) and an address where the operation requested by the command isoperated. The access signal terminals AT 38 may be the access signalterminals 26 in FIG. 1B. Each ASO 36 may provide the access requests ascommand signals and address signals, for example, to the coupled channelvia the corresponding TSVA 34. In a normal read operation, a readrequest and corresponding address information are externally provided tothe ASO 36 via the AT 38. The ASO 36 may provide the read request andthe corresponding address information to the coupled channel via theTSVA 34, responsive to the read request. The coupled channel may providethe data to the DI/O 35 via the TSVD 33 in response to the read requestand the corresponding address information. The DI/O 35 may provide thedata via the DT 37. Similarly, in a normal write operation, a writerequest and corresponding address information are externally provided tothe ASO 36 via the AT 38. The ASO 36 may provide the write request andthe corresponding address information to the coupled channel via theTSVA 34, responsive to the write request. At the same time, the DI/O 35may receive write data from the DT 37 and provide the write data to thecoupled channel via the TSVD 33 responsive to the write request and thecorresponding address information. Each of the channel interface blocksCIF_A 32 a, CIF_B 32 b, . . . and CIF_H 32 h may further include a datacomparator circuit DCMP 39 and an access signal comparator circuit ACMP40. Functionalities of the DCMP 39 and the ACMP 40 will be providedlater in detail.

The interface circuit 31 may further include a memory built-in self-testblock mBIST 41. The mBIST 41 may provide test signals to the channelinterface blocks CIF_A 32 a, CIF_B 32 b, . . . and CIF_H 32 h via amultiplexer MUX 45 in order to perform test operations on each channelresponsive to test control signals TCTL. The TCTL are externallyprovided via test control terminals TCT 43. The TCT 43 may be the testcontrol terminals 24 in FIG. 1B. The mBIST 41 may perform defective celldetection and repair functions during an initialization operation and anormal operation following the initialization operation, such as readand write operations, as well as during a test operation.Functionalities of the mBIST 41 will be provided later in detail. Theinterface circuit 31 may further include a power detection circuit PD42. The PD 42 may provide a power on signal PON to the mBIST 41responsive to power supply PS externally provided via a power terminalPT 44. The mBIST 41 may start the initialization operation in responseto the PON. The interface circuit 31 may further include test terminalsTT 46 and test pads TP 47. The TT 46 may be coupled to a socket or thelike in order to couple an external tester (not shown) to the interfacecircuit 31. The TP 47 may couple an external tester (not shown) having aprobe card interface, for example, to the interface circuit 31. The TP47 may be used for a test during wafer process. The MUX 45 may selectone of the TT 46, the TP 47 and the mBIST 41 as a source of the testsignals and provide the test signals to the channel interface blocksCIF_A 32 a, CIF_B 32 b, . . . and CIF_H 32 h.

In FIG. 2, the terminals, such as the DT 37, the AT 38, the TCT 43, thePT 44 and the TT 46 represented by circles may be formed by micro bumpelectrodes, for example. The test pad TP 47 may be formed by a padelectrode, for example. Each of the DT 37, the AT 38, the TCT 43, the PT44 and the TT 46 may include one or more terminals. The TP 47 mayinclude one or more pads.

FIG. 3 is a block diagram of the interface circuit 31 in FIG. 2including the memory Built-In Self Test (mBIST) circuit 41 in thesemiconductor device in accordance with an embodiment of the presentdisclosure. FIG. 3 shows a connection between mBIST 41 of FIG. 2 and oneof the channel interface blocks CIF_A 32 a, CIF_B 32 b, . . . and CIF_H32 h of FIG. 2 as an example. The other channel interface blocks may becoupled to the mBIST 41 similarly as shown in FIG. 3. The interface chipmay include a plurality of TSVD[n:0] 33 and corresponding DI/O[n:0] 35,DT[n:0] 37 and DCMP[n:0] 39 provided with a single channel. Similarly,the interface chip may include a plurality of TSVA[m:0] 34, ASO[m:0] 36,AT[m:0] 38 and ACMP[m:0] 40 provided with a single channel. In FIG. 3,“m” is a number of bits for command/address signals and “n” is a numberof bits for data signals, and “m” and “n” may be different from eachother. The mBIST 41 may include an mBIST logic circuit mBISTL 411 and astorage area MEM 412. The mBISTL 411 may be a control circuit, such asan algorithmic pattern generator (APG), which may control operations ofthe mBIST 41. The MEM 412 may be a single memory circuit. Alternatively,the MEM 412 may be a plurality of memory circuits, each of which mayperform independent functions individually. For example, the MEM 412 mayinclude error catch memories (ECMs) and microcode memories (MCMs). Forexample, each of the ECMs and the MCMs may include static random accessmemories (SRAMs). The MCMs may store microcodes. The microcodes mayrepresent test patterns for testing the memory cells of the core chips.The mBISTL 411 may perform test operations in accordance with themicrocodes. The ECMs may store defective address information during thetest operations. For example, the MEM 412, such as the ECMs and/or theMCMs, can be used as spare cells for repairing defective memory cells inthe core chips 22 as described later in detail. In some embodiments, theI/F chip 21 may further include a read only memory (ROM) to store themicrocodes. In another embodiment, initial states of the MCMs in the MEM412 may represent the microcodes.

In one embodiment, the mBIST 41 may operate during the test operations.The mBIST 41 may further operate during the initialization operation andthe normal operation. In particular, the mBIST 41 may detect one or moredefective cells among memory cells of core chips 22. Upon detection ofthe one or more defective cells, the mBIST 41 may store addressinformation for the defective cells in one portion of the MEM 412, forexample the ECMs and/or MCMs, during the initialization operation.Furthermore, in the normal operation, the mBIST 41 may use an otherportion of the MEM 412, for example, the ECMs and/or MCMs, to replacethe defective cells with the other portion of the MEM 412 which mayserve as spare memory. In other words, the mBIST 41 may redirect accessto the defective cells of the core chips 22 to the other portion of theMEM 412.

In some embodiments, each of the core chips 22 may further include adefective address storing circuit, such as anti-fuses and spare memorycells. When the core chips 22 include the defective address storingcircuit, the other portion of the MEM 412 of the I/F chip 21 and thespare memory cells of the core chips 22 may be used for repairingdifferent defective cells from each other. In some embodiments, theother portion of the MEM 412 of the I/F chip 21 may replace thedefective cells of the spare memory cells of the core chips 22. Thedetailed operation of the mBIST 41 and the channel interface block 32during each of the test operation, the initialization operation and thenormal operation including a read operation or a write operation aredescribed below.

1) Test Operation

FIG. 4A is a simplified flow diagram of a test operation process by themBIST in FIG. 3 in the semiconductor device in accordance with anembodiment of the present disclosure. For example, the test operationprocess may be performed by the mBIST before shipping.

In an operation block 401, the mBIST 41 may receive the test controlsignals TCTL externally provided through the test control terminals TCT43. The test control signals may include a test instruction. In responseto the TCTL, the mBISTL 411 may execute the microcodes to perform a testoperation. In some embodiments, the microcodes may be prestored on theMCMs or a ROM of the I/F chip 21 as their initial states. In otherembodiments, the MCMs may store the microcodes externally provided. ThemBISTL 411 may provide a test enable signal TEST to the DI/O[n:0] 35 andthe ASO[n:0] 36. The DI/O[n:0] 35 may couple, in response to the TEST,the TSVD[n:0] 33 to a BISTDATA node coupled to the DCMP[n:0] 39 and themBIST 41 while decoupling the external data terminal DT[n:0] 37 from theDCMP[n:0] 39 and the mBIST 41. Similarly, the ASO[m:0] 36 may couple, inresponse to the TEST, the TSVA[m:0] 34 to a BIST command and addressnode BISTC/A coupled to the ACMP[m:0] 40 and the mBIST 41 whiledecoupling the external access terminal AT[m:0] 38 from the ACMP[m:0] 40and the mBIST 41. The detailed description of the DI/O[n:0] 35 and theASO[m:0] 36 will be provided later referring to FIGS. 5 and 6.

In an operation block 402, the mBISTL 411 may provide test write dataTWDATA[n:0] to the DI/O[n:0] 35. The mBISTL 411 may provide a testcommand/address signal TC/A[m:0] including test write commands and testaddress information to the ASO[m:0] 36. Accordingly, the DI/O[n:0] 35and the ASO[m:0] 36 may perform test write operations on the respectivechannel. For example, the DI/O[n:0] may provide the TWDATA[n:0] as coredata COREDATA[n:0] to the TSVD[n:0] 33. The ASO[m:0] 36 may provide theTC/A[m:0] as a core command and address signal COREC/A[m:0] to theTSVA[m:0] 34.

After the COREDATA[n:0] are stored in memory cells designated by theCOREC/A[m:0] in the respective channel of the core chips 22, the mBISTL411 may provide the test command/address signal TC/A[m:0] test includingread commands and test address information to the ASO[m:0] 36 to performtest read operations in an operation block 403. The mBISTL 411 mayprovide a memory control signal MEMCTL including the test addressinformation TA to the MEM 412. Accordingly, the ASO[m:0] 36 may providethe COREC/A[m:0] including the test read commands and the test addressinformation to the respective channel via the TSVA[m:0] 34. Therespective channel may provide the COREDATA[n:0] including test readdata to the TSVD[n:0] 33 responsive to the COREC/A[m:0]. The DI/O[n:0]35 may receive the test read data and provide the test read data to theDCMP[n:0] 39.

In an operation block 404, the DCMP[n:0] 39 may compare the test readdata with the expected data EXP[n:0] that is the corresponding testwrite data provided from the mBISTL 411. The DCMP[n:0] 39 may provide acomparison result DCMR[n:0] to an error detection circuit PFD 48. If atleast one DCMR[n:0] is indicative of data discrepancy between the testread data and the EXP[n:0], the PFD 48 may provide an active faildetection signal P/F (e.g., at a logic high level) in an operation block406. If there is no data discrepancy between the test read data and theEXP[n:0] for all the DCMR[n:0], the PFD 48 may provide an inactive P/F(e.g., at a logic low level). In response to the active P/F, the MEM 412may store the corresponding test address information as defectiveaddress information in an operation block 406.

After testing the memory cells of the respective channel, determineddefective address information stored in the MEM 412 may be programmedinto a defective address storing circuit, for example anti-fuses, of thecore chips 22 in an operation block 407. The determined defectiveaddress information may be read out from the MEM 412 to an externaltester or an external controller (not shown) before programming in anoperation block 405. The programming of the defective addressinformation may be performed by mBISTL 411 or externally by the testeror the controller.

2) Initialization Operation

FIG. 4B is a simplified flow diagram of a test operation as a part of aninitialization operation process performed by the mBIST in thesemiconductor device in accordance with an embodiment of the presentdisclosure. The test operation as the part of the initializationoperation process is similar to the test operation before shippingdescribed above except a power on sequence. In an operation block 421,the mBISTL 411 may respond to a power on signal PON instead of the TCTLin order to initiate testing of the memory cells. In some embodiments,the TCTL may be used to initiate testing in an operational block 401′that is similar to the operation block 401 in FIG. 4A. In the testoperation as the part of the initialization operation process, theprogramming of the determined defective address information into thedefective address storing circuit of the core chips 22 may be skipped.Instead, the determined defective address information may be stored inthe MEM 412 of the I/F chip 21 in an operation block 406′, afterexecuting the test write in an operation block 402′, similar to theoperation block 402, the test read in an operation block 403′ similar tothe operation block 403 and the comparison of the test read data and theexpected data EXP[n:0] in an operation block 404′ that is similar to theoperation block 404. In an operation block 422, the normal accessoperation, including a write operation and a read operation, may followthe initialization operation.

3) Normal Write Operation

In the normal operation, the TEST may be inactive (e.g., at a logic lowlevel). The DI/O[n:0] 35 may couple the TSVD[n:0] 33 to the DT[n:0] 37until hit signals Hit_R/W become active (e.g., at a logic high level).The detailed description of the DI/O[n:0] 35 will be provided laterreferring to FIG. 5. An external memory controller (e.g., the memorycontroller 11 of FIG. 1B) may provide external data signals EXDATA[n:0]including write data to the DT[n:0] 37. The external memory controllermay also provide an EXC/A[m:0] signal including a write command andaccess address information (e.g., write address information) to theAT[m:0] 38. The ASO[m:0] 36 may provide the EXC/A[m:0] as theCOREC/A[m:0] to the respective channel. In this embodiment, the ASO[m:0]36 may further provide the EXC/A[m:0] on the BISTC/A node to theACMP[m:0] 40. The ACMP[m:0] 40 may compare the access addressinformation on the BISTC/A node with the defective address informationDEFAIF[m:0] provided from the MEM 412. The ACMP[m:0] 40 may provide acomparison result ACMR[m:0] to a hit detection circuit HITD 49. When allACMR[m:0] are indicative of a match between the access addressinformation and the DEFAIF[m:0], the HITD 49 may provide a HIT signal tothe mBISTL 411. In some embodiments, the MEM 412 may provide theDEFAIF[m:0] to the ACMP[m:0] 40. The ACMP[m:0] 40 may include latchcircuits, for example, which may hold the DEFAIF[m:0] at least duringthe normal operation (e.g., the write operation or the read operation).The HIT signal may indicate that the provided address informationcorresponds to the defective address information. The HIT signal mayalso indicate a type of the operation (e.g., the write operation). Inresponse to the HIT, the mBIST 41 may provide a HIT_W signal to theDI/O[n:0] 35. Responsive to the HIT_W signal, the DI/O[n:0] 35 providesthe EXDATA[n:0] on the BISTDATA node to the MEM 412. The mBISTL 411 mayperform the write operation on the MEM 412 to store the write date intothe MEM. In some embodiments, the mBISTL 411 may stop performing a writeoperation on the respective channel on the core chip 22 while the repairoperation, such as redirecting the access to the MEM 412, is beingperformed. When the address information on the BISTC/A node does notcorrespond to the DEFAIF[m:0], the DI/O[n:0] 35 may provide theEXDATA[n:0] to the channel as the COREDATA[n:0] and the COREDATA[n:0]are written into the corresponding memory cells of the core chip 22.

4) Normal Read Operation

The normal read operation is similar to the normal write operationdescribed above except a reading sequence. In the read operation, themBISTL 411 may provide the HIT_R signal in response to the HIT signalprovided from the HITD 49 when any ACMR[m:0] is indicative of a matchbetween the access address information (e.g., read address information)and the DEFAIF[m:0]. Responsive to the HIT_R signal, the DI/O[n:0] 35may couple the DT[n:0] 37 to the MEM 412 through the BISTDATA node. ThemBISTL may further perform the read operation on the MEM 412 to providerequested read data from the MEM 412. In some embodiments, the mBISTL411 may control a read latency for the read data. The read dataretrieved from the MEM 412 may be provided to the DI/O[n:0] 35 via theBISTDATA node. The DI/O[n:0] 35 may selectively couple the BISTDATA nodeto the EXDATA node responsive to the active HIT_R signal, thus theDI/O[n:0] 35 may provide the read data to the DT[n:0] 37. In someembodiments, the mBISTL 411 may stop performing a read operation on therespective channel on the core chip 22 while the repair operation, suchas redirecting the access to the MEM 412 for reading, is beingperformed. When the address information on the BISTC/A node does notcorrespond to the DEFAIF[m:0], the data may be retrieved from the memorycells of the respective channel of core chip 22 to the DT[n:0] 37.

FIG. 5 is a schematic diagram of the data input/output circuit (DI/O) 35of FIG. 3, in accordance with an embodiment of the present disclosure.The DI/O 35 is coupled to the EXDATA node. The DI/O 35 may include areceiver buffer Rx 50. The receiver buffer Rx 50 receives the EXDATAfrom the DT 37 and may further provide the EXDATA to one input node of aselector 55. The selector 55 may further receive BISTDATAout on theBISTDATA node from the DCMP 39 at another input node. The selector 55may further receive the TEST from the mBIST 41 at a select node afterinversion. The TEST may be active in the test operation and inactive inthe normal operation (e.g., a write operation, a read operation, etc.).If the TEST is inactive, the selector 55 may provide the EXDATA to abuffer circuit 57. If the TEST is active, the selector 55 may providethe BISTDATAout from the BISTDATA node to the buffer circuit 57. Forexample, the buffer circuit 57 may be a tri-state buffer. An input nodeof the buffer circuit 57 may receive a signal from the selector 55. Anenable input node of the buffer circuit 57 may receive a write enablesignal CORE_W, indicative of enabling writing data to the core chips 22.For example, the CORE_W may be provided as a portion of the COREC/A bythe ASO 36 in response to a write command. The buffer circuit 57 mayprovide the signal from the selector 55 as the COREDATA when the CORE_Wis active (e.g., a logic high level). The DI/O 35 may include a selector56 and a NAND circuit 56 a coupled to one input node of the selector 56.The NAND circuit 56 a may receive a HIT_W signal and the signal from theselector 55. The NAND circuit 56 a may provide the signal from theselector 55 to the one input node of the selector 56 responsive to theactive HIT_W signal. The selector 56 may have another input node thatmay receive the output signal of the buffer circuit 57 provided as theCOREDATA. The selector 56 may further receive the TEST from the mBIST 41at a select node after inversion. When the TEST is active, the selector56 may provide the signals in parallel from the selector 55 via thebuffer circuit 57, the same data as the COREDATA as BISTDATAin throughthe BISTDATA node to the DCMP 39. When the HIT_W is active while theTEST is inactive, the selector 56 may provide the EXDATA as theBISTDATAin through the BISTDATA node to the DCMP 39. In the normal writeoperation without defective address information, the TEST and the HIT_Wboth are inactive. Thus, no data may be provided from the selector 45.Thus, merely the EXDATA may be provided as the COREDATA through theselector 55 and the buffer circuit 57.

A selector 54 may receive the BISTDATAout and the COREDATA. The selector54 may further receive the HIT_R at a select node from the mBIST 41. Theselector 55 may provide the BISTDATAout if the HIT_R is active. Theselector 54 may further provide the COREDATA if the HIT_R is inactive. Atransmitter buffer 51 may provide the output signal in series as theEXDATA.

FIG. 6 is a schematic diagram of the access signal output circuit (ASO)36 of FIG. 3, in accordance with an embodiment of the presentdisclosure. The ASO 36 may include a receiver buffer Rx 58. The receiverbuffer Rx 58 receives the EXC/A from the AT 38. The selector 60 mayfurther receive the TC/A from the mBIST 41 at another input node. Theselector 60 may further receive the TEST from the mBIST 41 at a selectnode. The TEST may be active in the test operation and inactive in thenormal operation. If the TEST is inactive, the selector 60 may providethe EXC/A as the COREC/A. If the TEST is active, the selector 60 mayprovide the TC/A as the COREC/A. An AND circuit 61 may receive outputsignals of the selector 60. The AND circuit 61 may further receive theTEST from the mBIST 41 after inversion. The TEST after the inversionbecome inactive responsive to the active TEST, and the BISTC/A nodebecomes inactive. The AND circuit 61 may provide the EXC/A received fromthe selector 60 responsive to the inactive TEST to the BISTC/A.

FIGS. 7A and 7B are schematic diagrams of a portion of the storage areaMEM 412 of FIG. 3, in accordance with an embodiment of the presentdisclosure. For example, the MEM 412 may include error catch memories(ECMs) 70. In the test operation, the ECMs 70 may receive test addressinformation TA included in the MEMCTL and the fail signal P/F. The ECMs70 may store the TA as failure information including defective addressinformation, responsive to the active fail signal P/F. In the normaloperation, the ECMs 70 may have a plurality of portions, including aportion 71 a and a portion 71 b. The portion 71 a of the plurality ofportions of ECMs 70 may store the failure information. The failureinformation may be detected and stored during the initializationoperation, as earlier described. The defective address informationDEFAIF may be provided from the portion 71 a to a corresponding ACMP 40.The portion 71 b of the plurality of portions of ECMs 70 may includespare memory cells that may replace defective memory cells of the corechips 22 addressed by the failure information. The portion 71 b of theplurality of portions of ECMs 70 may receive a control signal R/WCTL inthe MEMCTL indicative of the read operation or the write operation. Theportion 71 b may include one or more spare memory cells that may storedata from the BISTDATA node responsive to the TA and the R/WCTLindicative of the write operation, in the write operation. The portion71 b may provide data from the one or more spare memory cells to theBISTDATA node responsive to the TA and the R/WCLTL indicative of theread operation, in the read operation.

FIG. 7C is a schematic diagram of a portion of the MEM of FIG. 3, inaccordance with an embodiment of the present disclosure. In thisembodiment, the ECMs 70 may further include a page buffer PB 72, whichmay buffer data between the spare memory cells in the portion 71 b andthe DUO 35. The PB 72 may include a plurality of flip-flops, forexample, which may provide access speed higher than access speed of theECMs 70.

FIG. 7D is a schematic diagram of a portion of the MEM of FIG. 3, inaccordance with an embodiment of the present disclosure. In thisembodiment, the ECMs 70 may further include anti-fuses AF 73 topermanently store the failure information.

FIG. 8 is a block diagram of the I/F chip 31 including a memory Built-InSelf Test (mBIST) circuit 41 in the semiconductor device in accordancewith an embodiment of the present disclosure. Description of componentscorresponding to components included in and previously described withreference to FIG. 3 will not be repeated. Unlike the I/F chip of FIG. 3,the HITD 49′ may control read and write operations on the MEM 412′instead of the mBISTL 411′. The HITD 49′ may provide a portion of theMEMCTL signals, such as the TA and the R/WCTL to the MEM 412′, when allACMR[m:0] are indicative of a match between the access addressinformation (e.g., read address information) and the DEFAIF[m:0]. Inthis example, the HITD 49′ may directly provide the HIT_R and the HIT_Wto the DI/O[n:0] 35′ instead of providing the HIT to the mBISTL 411′ andhaving the mBISTL 411′ providing the HIT_R and the HIT_W.

FIG. 9 is a schematic diagram of one core chip of the plurality of corechips 22 in the semiconductor device in accordance with an embodiment ofthe present disclosure. The one core chip may include an access controlcircuit AC 80, a memory cell array MA 82, a spare memory cell array SMA83 and a defective address storing circuit AF 81. For example, thedefective address storing circuit AF 81 may include anti fuses. In someembodiments, memory cells in the MA 82 and memory cells in the SMA 83may be different in type from the memory cells in the MEM 412 of the I/Fchip 21. For example, the memory cells in the MA 82 and the memory cellsin the SMA 83 may be DRAM memory cells. The SMA may include a pluralityof spare memory cells to replace the defective memory cells in thememory cell array as described earlier. The AF 81 may store failureinformation, including defective address information. As describedabove, the MEM 412 of the I/F chip 21 may also store defective addressinformation. The defective address information stored in the MEM 412 ofthe I/F chip 21 and the defective address information stored in the AF81 of each core chip 22 may be different from each other. In someembodiments, the defective address information detected during a testoperation may be stored into the AF 81 of each core chip 22 while thedefective address information detected during an initializationoperation may be stored into the MEM 412 of the I/F chip 21. In someembodiments, the AF 81 may store the defective address information formemory cells in the MA 82 on the same core chip 22, while the MEM 412 ofthe I/F chip 21 may store the defective address information for cellsplaced in any core chip 22 in the semiconductor device. The AC 80 mayperform read and write operations on the MA 82 in response to theCOREC/A via the TSVA 34 and the COREDATA via the TSVD 33. The AC 80 mayaccess memory cells in SMA 83 when the COREC/A includes the accessaddress information that corresponds with one or more addresses includedof the defective address information in DEFADDC provided from the AF 81.

FIG. 10 is a block diagram of the I/F chip including a memory Built-InSelf Test (mBIST) circuit in the semiconductor device in accordance withan embodiment of the present disclosure. The I/F chip 21 may include acommand decoder 1002, which may be included in the access signal outputcircuit ASO 36 in FIG. 3. The command decoder 1002 may receivecommand/address signals CA via an input buffer Rx, and may furtherprovide write command information (WriteCom), read command information(ReadCom) and an address to one or more core chips 22 through a signalline 23 implemented as a through substrate via (TSV) (e.g., TSVA 34 inFIG. 1B). The I/F chip 21 may include a controller circuit 1001 and anmBIST circuit 41′ which includes an mBIST logic circuit 411′ and astorage area MEM 412′. The MEM 412′ may include a plurality of memorycircuits 1004 and 1005. For example, the plurality of memory circuits1004 and 1005 may be static random access memories (SRAMs) and onememory circuit 1004 of the plurality of memory circuits 1004 and 1005may include a CAM memory that may function in acontents-addressable-memory (CAM) mode. The controller circuit 1001 maycontrol the memory circuit 1004 through a flag memory 1003. Thecontroller circuit 1001 may receive the WriteCom and the ReadCom. Thecontroller circuit 1001 may also receive HIT signal from a storage areaMEM 412′. The controller circuit 1001 may also receive flag informationfrom a flag memory 1003. For example, the flag information may includein-use flag information and locked flag information. The in-use flaginformation may indicate that an area with the CAM mode corresponding toa particular address provided in the memory circuit 1004 is already inuse. The locked flag information may indicate that an area in the CAMmode corresponding to a particular address provided in the memorycircuit 1004 is locked and unmodifiable (e.g., already storing thedefective address information). The memory circuit 1005 may provide datastored on the memory circuit 1005 on a RAMDAT node (e.g., the BISTDATAnode in FIG. 3). A multiplexer MUX 1006 and a multiplexer MUX 1007,which may function as the DI/O[n:0] 35 in FIG. 3, receive the data fromthe RAMDAT node. The MUX 1007 may receive data read from the core chip22 via a TSV 23 (e.g., TSVD 33 in FIG. 1B) via a ReadData node. The MUX1007 provides an output signal to a data queue DQ node via an outputbuffer Tx, responsive to the HIT signal from the memory circuit 1004. Ifthe HIT signal is active (e.g., a logic high level) indicative that theRAMDAT is to be provided, the MUX 1007 may provide the data from theRAMDAT node. The MUX 1007 may provide the read out data from the corechip 22 via the ReadData node if the HIT signal is inactive (e.g., alogic low level) and no replacement data is stored in the MEM 412′ forthe particular address. The MUX 1006 receives the data from the RAMDATnode as well as test data from the mBIST logic circuit 411′ and provideseither the data from the RAMDAT node or the test data as expected dataon an EXPDAT (e.g., the EXP in FIG. 3) node to a comparator 1008,responsive to whether the data is to be matched with the data from theMEM 412′ or the test data from the mBIST logic circuit 411′ (e.g., thetest write data TWDATA in FIG. 3). The comparator 1008 (e.g., the DCMP39 in FIG. 3) compares the expected data the EXPDAT node and theReadData and provides comparison result signal CMPRSLT (e.g., the P/F inFIG. 3) to the controller circuit 1001 and the mBIST logic circuit 411′.Either the controller circuit 1001 or the mBIST logic circuit 411′ maysend control signals (Ctrl) to set the in-use flag information and thelocked flag information in the flag memory 1003.

In write operations, the controller circuit 1001 may write an addressprovided along with the WriteCom into the memory circuit 1004 inresponse to the WriteCom, the in-use flag information, the locked flaginformation and the HIT signal. For example, the memory circuit 1004 maystore the address in the CAM memory and may further provide an inactiveHIT signal to the memory circuit 1005 and the controller circuit 1001,if the address is not stored in the CAM memory in the memory circuit1004. The memory circuit 1004 may provide an active HIT signal to thememory circuit 1005 and the controller circuit 1001, if the address isalready stored in the CAM memory in the memory circuit 1004. The memorycircuit 1005 may store data provided from the data queue DQ node via aninput buffer Rx on a WriteData node, responsive to the HIT signal. Forexample, the memory circuit 1005 may store data on the WriteData node inan area addressed by a newly allocated address, if the HIT signal isinactive. The memory circuit 1005 may store the data on the WriteDatanode in an area already allocated corresponding to the address, if theHIT signal is active. Data on the WriteData node may be also provided torespective memory cells of the core chip 22. In some embodiments, dataon the WriteData node may not be provided to the respective memory cellsof the core chip 22 if the corresponding address have been held andlocked in the CAM memory. The controller circuit 1001 may preventwriting the address if the in-use flag information or the locked flaginformation for all addresses in the memory circuit 1004 may indicatethat all of the CAM memory in the memory circuit 1004 is already in-useor locked and thus unavailable.

FIG. 11A is a simplified flow diagram of a write operation in the I/Fchip of FIG. 10, in accordance with an embodiment of the presentdisclosure. Upon receiving a write command at the command decoder 1002(S1100), the controller circuit 1001 may provide the address along withthe WriteCom to the flag memory 1003 and the flag memory 1003 mayprovide the address to the memory circuit 1004 on a CAMWE signal. Thememory circuit 1004 may determine whether the address is already storedin the CAM memory and may further provide the HIT signal to thecontroller circuit 1001 and the memory circuit 1005. The memory circuit1005 may check whether the HIT signal is active (S1101) and may furtherstore the data on the WriteData node if the HIT signal is active(S1106). If the HIT signal is not active “N”, the controller circuit1001 may check the in-use flag information and the locked flaginformation (S1102). If the in-use flag information and the locked flaginformation are indicative that all the CAM memory is used (CAMoverflow), the controller circuit 1001 may skip writing the address inthe CAM memory in the memory circuit 1004 and may end the writingoperation (S1107).

Optionally, the controller circuit 1001 may skip writing the address inthe CAM memory in the memory circuit if the address is related to systemdefined conditions (S1103). For example, the system defined conditionsmay include an address sampling. The address sampling condition mayinclude random sampling, the addresses which tend to be accessedfrequently, the addresses in a same area (e.g., the same core, the samechannel, etc.) having a frequent repair history and thus a higherdeficiency rate than other area, or the addresses in a predeterminedrange due to system configuration (e.g., having a small margin).Alternatively, it is possible to have an additional counter having acount of the additional counter may be changed at a predeterminedinterval to point a next address in the core dies to be stored forchecking the deficiency. Alternatively, it is possible to write theaddress to overwrite an oldest address stored in the CAM memory (afterskipping the step S1102). Depending on the steps S1102 and S1103, thecontroller circuit 1001 may write the address to the CAM memory (S1105)and set in-use flag information of the address. The memory circuit 1005stores the data on the WriteData node along with the address and theWriteCom (S1106) if the HIT signal is active or if the controllercircuit 1001 writes the address to the CAM memory and the writeoperation is completed (S1107).

In read operations, the memory circuit 1004 may compare the addressprovided along with the ReadCom with addresses stored in the CAM memory.The memory circuit 1004 may provide the active HIT signal to the memorycircuit 1005 if the address is found in the addresses in the CAM memory.The multiplexer MUX 1007 may provide either the data on the RAMDAT nodeor ReadData from the core chip 22 via the TSV 23 to the data queue DQvia an output buffer Tx, responsive to the active HIT signal. Asdescribed earlier, the comparator 1008 may compare the ReadData with thedata on the RAMDAT node and may further provide the CMPRSLT signal. Thecontroller 1001 may control the flag memory 1003 to change the in-useflag information of the address inactive (e.g., “0”), if the CMPRSLTsignal indicates that the data on the RAMDAT node match the ReadData.Thus, the CAM memory which has stored the address is freed and becomesavailable to store a new address. If the CMPRSLT signal indicates thatthe data on the RAMDAT node do not match the ReadData, locked flaginformation of the address active (e.g., “1”) to prevent the CAM memoryof the address from overwriting a new address. As a result, the CAMmemory may store the address as the defect address information and theread/write operation of the address in the core chip 22 may beredirected permanently to the memory circuit 1005 in the MEM 412′.

FIG. 11B is a simplified flow diagram of a read operation in the I/Fchip of FIG. 10, in accordance with an embodiment of the presentdisclosure. Upon receiving a read command at the command decoder 1002(S1100), the controller circuit 1001 may provide the address along withthe ReadCom to the flag memory 1003 and the flag memory 1003 may providethe address to the memory circuit 1004 on a CAMWE signal. The memorycircuit 1004 may determine whether the address is already stored in theCAM memory and may further provide the HIT signal to the controllercircuit 1001, the memory circuit 1005 and the multiplexer MUX 1007. TheMUX 1007 may check whether the HIT signal is active (S1111) and mayfurther provide the ReadData from the core chip 22 via the TSV 23, ifthe HIT signal is inactive “N” (S1112) and the write operation iscompleted (S1118). If the HIT signal is active “Y”, the MUX 1007 mayprovide the data on the RAMDAT node to the data queue DQ (S1113). Thecomparator 1008 may compare the ReadData with the data on the RAMDATnode with and may further provide the CMPRSLT signal (S1116). Thecontroller 1001 may control the flag memory 1003 to change the in-useflag information of the address inactive (e.g., “0”), if the CMPRSLTsignal indicates that the data on the RAMDAT node match the ReadData(S1116) and the read operation is completed (S1118). Thus, the CAMmemory which has stored the address is freed and becomes available tostore a new address. If the CMPRSLT signal indicates that the data onthe RAMDAT node do not match the ReadData, the flag memory 1003 may setlocked flag information of the address active (e.g., “1”) to prevent theCAM memory of the address from overwriting a new address (S1117) and theread operation is completed (S1118).

FIG. 12 is a block diagram of the I/F chip in the semiconductor devicein accordance with an embodiment of the present disclosure. Descriptionof components corresponding to components included in and previouslydescribed with reference to FIG. 10 will not be repeated. The I/F chip21 may include a storage area MEM 1200 including a plurality of memorycircuits 1204 and 1205. For example, the plurality of memory circuits1204 and 1205 may be static random access memories (SRAMs) and onememory circuit 1204 of the plurality of memory circuits 1204 and 1205may include a CAM memory that may function in acontents-addressable-memory (CAM) mode. The controller circuit 1001 maycontrol the memory circuit 1204 through a flag memory 1003. Thecontroller circuit 1001 may receive a WriteCom and a ReadCom. Thecontroller circuit 1001 may also receive HIT signal from a storage areaMEM 1200. The controller circuit 1001 may also receive flag informationfrom a flag memory 1003. For example, the flag information may includein-use flag information and locked flag information. The in-use flaginformation may indicate that an area with the CAM mode corresponding toa particular address provided in the memory circuit 1204 is already inuse. The locked flag information may indicate that an area in the CAMmode corresponding to a particular address provided in the memorycircuit 1204 is locked and unmodifiable (e.g., already storing thedefective address information). The memory circuit 1205 may provide datastored on the memory circuit 1205 on a RAMDAT node (e.g., the BISTDATAnode in FIG. 3). A multiplexer MUX 1006 and a multiplexer MUX 1007,which may function as the DI/O[n:0] 35 in FIG. 3, receive the data fromthe RAMDAT node. The MUX 1007 may receive data read from the core chip22 via a TSV 23 (e.g., TSVD 33 in FIG. 1B) via a ReadData node. The MUX1007 provides an output signal to a data queue DQ node via an outputbuffer Tx, responsive to the HIT signal from the memory circuit 1204. Ifthe HIT signal is active (e.g., a logic high level) indicative that dataon the RAMDAT node is to be provided, the MUX 1007 may provide the datafrom the RAMDAT node. The MUX 1007 may provide the read out data fromthe core chip 22 via the ReadData node if the HIT signal is inactive(e.g., a logic low level) and no replacement data is stored in thememory circuit 1205 for the particular address. The MUX 1006 receivesthe data from the RAMDAT node as well as test data from the memorycircuit 1205 and provides either the data from the RAMDAT node or thetest data as expected data on an EXPDAT (e.g., the EXP in FIG. 3) nodeto a comparator 1008, responsive to whether the data is to be matchedwith the test data from the memory circuit 1205. The comparator 1008(e.g., the DCMP 39 in FIG. 3) compares the expected data the EXPDAT nodeand data read from the core chip 22 on the ReadData node and providescomparison result signal CMPRSLT (e.g., the P/F in FIG. 3) to thecontroller circuit 1001. The controller circuit 1001 may send controlsignals (Ctrl) to set the in-use flag information and the locked flaginformation in the flag memory 1003.

An I/F chip may include an error correction code (ECC) function. FIG. 13is a block diagram of the I/F chip in the semiconductor device inaccordance with an embodiment of the present disclosure. Description ofcomponents corresponding to components included in and previouslydescribed with reference to FIG. 10 will not be repeated. The I/F chip21 may include a storage area MEM 1300 including a plurality of memorycircuits 1304 and 1305. For example, the plurality of memory circuits1304 and 1305 may be static random access memories (SRAMs) and onememory circuit 1304 of the plurality of memory circuits 1304 and 1305may include a CAM memory that may function in acontents-addressable-memory (CAM) mode. The memory circuit 1304 mayinclude two ports Port1 1321 and Port2 1322. The port Port1 1321 mayreceive an address from a command decoder 1002 for accessing the CAMmemory. The port Port2 1322 may receive a control signal CAMWE and anerror address signal ERRADD. The memory circuit 1305 may include twoports Port1 1323 and Port2 1324. The port Port1 1323 may receive aWriteCom from the command decoder 1002 and may further receive data on aWriteData node from a data queue DQ node in a write operation. The portPort1 132 may receive a ReadCom from the command decoder 1002. The portPort2 1322 may receive the control signal CAMWE and a read data signalREDDAT. The controller circuit 1001 may provide a control signal Ctrl tocontrol the memory circuit 1304 through a flag memory 1003. The flagmemory 1003 may provide the control signal CAMWE to the port Port2 1322of the memory circuit 1304 and the plurality of memory circuit 1304 and1305. The controller circuit 1001 may receive HIT signal from thestorage area MEM 1300. The controller circuit 1001 may also receive flaginformation from the flag memory 1003. For example, the flag informationmay include in-use flag information and locked flag information. Thein-use flag information may indicate that an area with the CAM modecorresponding to a particular address provided in the memory circuit1304 is already in use. The locked flag information may indicate that anarea in the CAM mode corresponding to a particular address provided inthe memory circuit 1304 is locked and unmodifiable (e.g., alreadystoring the defective address information). The memory circuit 1305 mayprovide data stored on the memory circuit 1305 on a RAMDAT node (e.g.,the BISTDATA node in FIG. 3) through the port Port1 1323. A multiplexerMUX 1306, which may function as the DI/O[n:0] 35 in FIG. 3, receive thedata from the RAMDAT node.

The I/F die 21 may include a write error correction circuit (WECC) 1310which may generate a Write error correction code (WriteECC) based ondata on the WriteData node during a write operation and provide the ECCon a WriteECC node to the core chip 22 with the data on the WriteDatanode. The I/F die 21 may include read error correction circuit (RECC)1311 that may receive the data on the ReadData node and a Read errorcorrection code (ReadECC) from the core chip 22 via a TSV 23 (e.g., TSVD33 in FIG. 1B), check if there is an error based on the ReadECC and thedata read from the core chip 22 on the ReadData node, and may furthercorrect the error, if any, during read operations. The RECC 1311 circuitmay activate an ERR signal if there is the error, regardless of whethererror is correctable or uncorrectable.

The MUX 1306 may receive data REDDAT which is a data signal from theRECC 1311 and the data on the RAMDAT node. The MUX 1306 provides anoutput signal to the data queue DQ node via an output buffer Tx,responsive to the HIT signal from the memory circuit 1304. If the HITsignal is active (e.g., a logic high level) indicative that data on theRAMDAT node is to be provided, the MUX 1306 may provide the data fromthe RAMDAT node. The MUX 1306 may provide the read out data REDDAT whichmay be after the error correction at the RECC 1311, if the HIT signal isinactive (e.g., a logic low level) and no replacement data is stored inthe memory circuit 1305 for the particular address. The I/F die 21 mayalso include a first-in-first-out memory (FIFO) 1309 which may receivethe address and store the address during read operations responsive tothe ReadCom. The FIFO 1309 provides the address on an ERRADD node to theport Port2 1322 of the memory circuit 1304 responsive to the ERR signal.

FIG. 14A is a simplified flow diagram of a write operation in the I/Fchip of FIG. 13, in accordance with an embodiment of the presentdisclosure. Upon receiving a write command at the command decoder 1002(S1400), the controller circuit 1001 may provide the address along withthe WriteCom to the flag memory 1003 and the flag memory 1003 mayprovide the address to the plurality of the memory circuits 1304 on theCAMWE signal. The memory circuit 1304 may determine whether the addressis already stored in the CAM memory and may further provide the HITsignal to the controller circuit 1001, the memory circuit 1305. Thememory circuit 1305 may check whether the HIT signal is active (S1401)and may further store the data on the WriteData node if the HIT signalis active (S1402) and end the writing operation (S1403). If the HITsignal is not active “N”, the controller circuit 1001 may skip writingthe data and end the writing operation (S1403).

FIG. 14B is a simplified flow diagram of a read operation in the I/Fchip of FIG. 13, in accordance with an embodiment of the presentdisclosure. Upon receiving a read command at the command decoder 1002(S1410), the controller circuit 1001 may provide the address along withthe ReadCom to the flag memory 1003 and the flag memory 1003 may providethe address to the memory circuit 1304 on the CAMWE signal. The memorycircuit 1304 may determine whether the address is already stored in theCAM memory and may further provide the HIT signal to the controllercircuit 1001, the memory circuit 1005 and the multiplexer MUX 1306. TheMUX 1306 may check whether the HIT signal is active (S1411). If the HITsignal is active “Y”, the MUX 1306 may provide the data on the RAMDATnode to the data queue DQ (S1412). and the read operation is completed(S1417). The MUX 1306 may provide the data on the REDDAT node from theRECC 1311 to the data queue DQ (S1413), if the HIT signal is inactive“N”. The controller circuit 1001 may check whether the ERR signal fromthe RECC 1311 is active (S1414). If the ERR signal from the RECC 1311 isnot active “N”, the read operation is completed (S1417). If the ERRsignal is active “Y”, the controller circuit 1001 may check the in-useflag information and the locked flag information, responsive to the ERRsignal (S1415). If the in-use flag information and the locked flaginformation are indicative that all the CAM memory is used (CAMoverflow=“Y”), the controller circuit 1001 may skip writing the addressin the CAM memory in the memory circuit 1304 and may end the writingoperation (S1417). If the CAM memory is available (CAM overflow=“N”),the controller circuit 1001 may control the plurality of memory circuits1304 and 1305 by providing the CAMWE signal. The memory circuit 1304 maywrite the address to the CAM memory from the FIFO 1309 via the ERRADDnode (S1416), responsive to the CAMWE signal. The memory circuit 1305may store the data on the REDDAT node (S1416). The controller circuit1001 may further set in-use flag information of the address (S1416).After the step in S1416, the read operation is completed (S1417). Thus,it is possible to provide remedy with the CAM memory based on the resultof ECC function.

Logic levels of signals used in the embodiments described the above aremerely examples. However, in other embodiments, combinations of thelogic levels of signals other than those specifically described in thepresent disclosure may be used without departing from the scope of thepresent disclosure.

Although this invention has been disclosed in the context of certainpreferred embodiments and examples, it will be understood by thoseskilled in the art that the inventions extend beyond the specificallydisclosed embodiments to other alternative embodiments and/or uses ofthe inventions and obvious modifications and equivalents thereof. Inaddition, other modifications which are within the scope of thisinvention will be readily apparent to those of skill in the art based onthis disclosure. It is also contemplated that various combination orsub-combination of the specific features and aspects of the embodimentsmay be made and still fall within the scope of the inventions. It shouldbe understood that various features and aspects of the disclosedembodiments can be combined with or substituted for one another in orderto form varying mode of the disclosed invention. Thus, it is intendedthat the scope of at least some of the present invention hereindisclosed should not be limited by the particular disclosed embodimentsdescribed above.

What is claimed is:
 1. An apparatus comprising: at least one memory chipcomprising a plurality of first memory cells; and an interface chipcoupled to the at least one memory chip and comprising a control circuitand a storage area, wherein, during an initialization operation, thecontrol circuit is configured to detect one or more defective memorycells of the plurality of first memory cells of the at least one memorychip and, upon the detection of the one or more defective memory cells,to store first defective address information of the one or moredefective memory cells of the plurality of first memory cells into aportion of the storage area during the initialization operation, whereina remaining portion of the storage area serves as spare memory toreplace the one or more defective cells during a normal operation of theinterface chip and wherein the interface chip is configured to respond,at least in part, to the first defective address information and accessthe storage area in place of the at least one memory chip when theaccess request has been provided with respect to the one or moredefective memory cells of the plurality of first memory cells.
 2. Theapparatus as claimed in claim 1, wherein the control circuit isconfigured to perform a memory test operation in response to a power onsignal of the apparatus, and further configured to detect the one ormore defective memory cells of the first memory cells in the memory testoperation.
 3. The apparatus as claimed in claim 2, wherein the interfacechip further comprises a terminal that is configured to receive a testinstruction, wherein the control circuit is configured to perform thememory test operation in response to the test instruction.
 4. Theapparatus as claimed in claim 1, wherein the control circuit is furtherconfigured to perform a latency control on access the storage area. 5.The apparatus as claimed in claim 1, wherein the at least one memorychip comprises a defective address storing circuit in which seconddefective address information is stored, the second defective addressinformation of another one or more defective memory cells of the firstmemory cells of the at least one memory chip, wherein the firstdefective address information and the second defective addressinformation are different from each other.
 6. The apparatus as claimedin claim 5, wherein the control circuit is configured to detect theother one or more defective memory cells of the first memory cells toproduce the second defective address information configured to store thesecond defective address information in the storage area, and furtherconfigured to program the second defective address information into thedefective address storing circuit of the at least one memory chip. 7.The apparatus as claimed in claim 1, wherein the storage area comprisesa plurality of second memory cells that are different in type from thefirst memory cells.
 8. The apparatus as claimed in claim 1, wherein theat least one memory chip and the interface chip are stacked with eachother.
 9. The apparatus as claimed in claim 1, wherein the controlcircuit is configured to store access address information andcorresponding data into the storage area along with providing thecorresponding data to the at least one memory chip in a write operationand configured to respond to a read request to one or more cells of thefirst memory cells designated by the access address information tocompare the corresponding data stored in the storage area and thecorresponding data provided from the at least one memory chip todetermine whether the one or more cells of the first memory cellsdesignated by the access address information is defective or not. 10.The apparatus as claimed in claim 1, further comprising an errordetection circuit configured to receive data from one or more cells ofthe first memory cells and provide an error signal when the data includean error, and wherein the control circuit is configured to respond tothe error signal to identify the one or more cells as the one or moredefective cells and store access address information designating the oneor more cells into the storage area as the first defective addressinformation.
 11. The apparatus of claim 3, further comprising: a memorycontroller configured to provide the access request and write data tothe interface chip and further configured to receive read data from theinterface chip, wherein the memory controller is further configured toprovide the test instruction to the terminal of the interface chip. 12.An interface chip comprising: a test circuit comprising: a test logiccircuit; and one or more memories, wherein the test logic circuit isconfigured to detect one or more defective memory cells of at least onememory chip, during an initialization operation, when the test circuitis coupled to the at least one memory chip, wherein, upon detection ofthe one or more defective memory cells, a portion of the one or morememories are configured to store first address information of the one ormore defective memory cells as defective address information during theinitialization operation and a remaining portion of the one or morememories store spare memory to replace the one or more defective memorycells during a normal operation of the interface chip, and wherein thetest circuit is configured to access one or more memory cells in theremaining portion of the one or more memories responsive to an accessrequest, when the test logic circuit determines that the access requestincludes second address information relevant to the one or moredefective memory cells based on the defective address information. 13.The interface chip of claim 12, further comprising: an access signaloutput circuit configured to provide an operation command and thirdaddress information to the at least one memory chip; a data input/outputcircuit configured to receive test read data from the at least onememory chip and further configured to provide the test read data; a datacomparator circuit coupled to the data input/output circuit, configuredto compare the test read data with expected data and further configuredto provide a first comparison result; and an error detection circuitcoupled to the data comparator circuit and configured to provide a firstdetection signal responsive to the first comparison result to the testcircuit, wherein the test logic circuit is configured to provide a testread command as the operation command and test address information asthe address information to the access signal output circuit, and furtherconfigured to provide the expected data to the data comparator circuit,wherein the access signal output circuit is configured to provide thetest read command and the test address information to the at least onememory chip, and wherein the test circuit is configured to detect theone or more defective memory cells of the at least one memory chip basedon the first comparison result.
 14. The interface chip of claim 13,wherein the test logic circuit is further configured to provide testwrite data to the data input/output circuit and further configured toprovide a test write command as the operation command and the testaddress information as the address information to the access signaloutput circuit prior to providing the test read command, wherein theaccess signal output circuit configured to provide the test writecommand and the test address information to the at least one memory chipprior to providing the test read command, wherein the data input/outputcircuit is further configured to provide the test write data to the atleast one memory chip prior to receiving the test read data, and whereinthe expected data is the test write data.
 15. The interface chip ofclaim 13, further comprising: an access signal comparator circuitcoupled to the access signal output circuit, configured to compare thetest address information with the defective address information andfurther configured to provide a second comparison result; and a hitdetection circuit coupled to the access signal comparator circuit andconfigured to provide a second detection signal responsive to the secondcomparison result to the test circuit, wherein the test logic circuit isconfigured to determine that the access request includes addressinformation relevant to the one or more defective memory cells based onthe defective address information responsive to the second detectionsignal.
 16. The interface chip of claim 13, further comprising a testcontrol terminal coupled to a memory controller, wherein the testcircuit is configured to receive test control signals from the memorycontroller through the test control terminal, and further configured toconfigured to detect the one or more defective memory cells of the atleast one memory chip responsive to the test control signals.
 17. Theinterface chip of claim 13, further comprising a memory that isconfigured to store one or more microcodes, wherein the test logiccircuit is configured to execute the one or more microcodes to detectthe one or more defective memory cells of the at least one memory chip.18. A method of sharing error correction memory on an interface chip,comprising: detecting one or more defective memory cells of a memorychip during an initialization operation; upon detecting the one or moredefective memory cells, storing first address information of the one ormore defective memory cells as defective address information in aportion of the error correction memory during the initializationoperation, wherein a remaining portion of the error correction memoryserves as spare memory to replace the one or more defective memory cellsduring a normal operation of the interface chip; and accessing one ormore memory cells in the error correction memory responsive to an accessrequest including second address information relevant to the one or moredefective memory cells based on the defective address information. 19.The method of claim 18, wherein detecting the one or more defectivememory cells of the memory chip comprises: providing test write data,test access signal including test write commands and test addressinformation responsive to test control signals; providing the test writedata, test write commands and test address information to the memorychip including a memory cell corresponding to the test addressinformation; providing read commands and the test address information toa channel on the memory chip corresponding to the test addressinformation; receiving test read data from the channel; comparing thetest read data with expected data; and providing a comparison result,and wherein storing the first address information of the detected one ormore defective memory cells as the defective address information isexecuted responsive to the comparison result.
 20. The method of claim19, further comprising: receiving a power on signal, wherein thedefective address information is stored in a defective address storingcircuit responsive to the power on signal.
 21. The method of claim 20,wherein the defective address storing circuit is in the memory chip. 22.The method of claim 19, further comprising: receiving the test controlsignals including a test instruction, wherein the defective addressinformation is stored in the error correction memory responsive to thetest control signals.